Identifying Functions

Does this mapping diagram represent a function?

• No, because an input value goes to multiple output values
• Yes, because each input goes to one and only one output

What is the definition of a function?

• Has inputs and outputs

• Inputs have different outputs every time

• x-values and

  y-values

• Every input has only one output

• Yes
• No

• Yes
• No

Which set of ordered pairs is a function?

• {(9,5), (10,5), (9,-5), (10,-5)}

• {(3,4), (4,-3), (7,4), (3, 8)}

• {(6,-5), (7, -3), (8, -1), (9, 1)}

• {(2, -2), (5, 9), (5, -7), (1, 4)}

Is the relation a function? Why.

• Yes, because the x-value 11 has two y-values pair with it.
• Yes, because each x-value has only one y-value paired with it.
• No, because the x-value 11 has two y-values pair with it.
• No, because each x-value has only one y-value paired with it.

• Function
• Not a Function

Is this mapping a function or not a function?

• Function; the x's don't repeat

• Not a Function; the x's repeat

Which of these sets is not a function?

• { (2,3) , (3,5) , (4,9) }

• { (2,3) , (2,5) , (4, 9) }

• { (2,3) , (3,3) , (4,9) }

• Function
• Not a Function